MonoCalculus wrote:
I have two editions of "The Boy Electrician". The 1940's edition
is full of doing interesting things such as you describe, and
includes info on setting up your own X-Ray tubes with
attendant HT supplies!

The 1960's edition has been fully sanitised (Odd, because if
predates the Health and Safety paranoia by several years) and
all experiments revolve around 9 volt batteries.

They published a 1960's edition?!
The last version of TBE I saw was published in the '50s and
still had all the 'nasty' stuff. This version had a one tube
regenerative receiver using a 1H4G tube that was nearly obsolete
at the time. In fact, A. Morgan also published a set of books
called the Boy's 1st - 4th books of radio and electronics.
In the first book he had a similar radio, but in latter editions
of that book the tube was changed to a 6 volt 7 pin mini type.

Lindsay books (www.lindsaybks.com) is now selling a reprint in paperback
of the 40's BE, which has several radios using the type 30 tube
(same as 1H4G with 4 pin base). Except for the sections on radio,
the 40's and 50's editions are the same.